Active-matrix organic light emitting diode (AMOLED) panel cell testing circuit and method for repairing data lines via same

ABSTRACT

The application relates to an active-matrix organic light emitting diode (AMOLED) panel cell testing circuit and a method for repairing data lines via the AMOLED panel cell testing circuit. The application not only can achieve a screen detecting function of the cell testing circuit, but also achieve to repair the circuit and to improve panel yield.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the priority of International Application No.PCT/CN2019/087625 filed on 2019 May 20, which claims priority to ChineseApplication No. 201910357024.5, filed on 2019 Apr. 29. The entiredisclosures of each of the above applications are incorporated herein byreference.

BACKGROUND OF INVENTION Field of Invention

The present invention relates to a display field, and particularly to anactive-matrix organic light emitting diode (AMOLED) panel cell testingcircuit and a method for repairing data lines via the AMOLED panel celltesting circuit.

Description of Prior Art

Active-matrix organic light emitting diode (AMOLED) panels haveself-luminous properties and are made of a very thin organic materialcoating layer and a glass substrate. When an electric current passes,light is emitted from the organic materials. The AMOLED panels areself-illuminating, unlike thin film field effect transistor liquidcrystal display (TFT LCD) panels with backlights, have wide viewingangles, high color saturation, especially low driving voltage and lowpower consumption, fast response times, light weight, thin thickness,simple construction, low cost, and etc., and is regarded as one of themost promising products.

At present, product yield is still a key issue of AMOLED technology. Formonitoring different process yields, detection circuits are placed inthe panels for screening normal panels during the different processes,thereby to decrease defective products flowing into the latter processstages. Cell testing circuit is a common detection circuit and isconfigured for detect panels in a cell process.

In a typical AMOLED panel, the cell testing circuit can only be used asa circuit for detecting the panel display. Referring to FIG. 1, it is aschematic diagram of a conventional cell testing circuit, which usesmore traces and is placed in a larger space, which is disadvantageous toa narrow bezel design of a panel, and mainly includes six thin filmtransistors T1 to T6 as switches, gates of T1-T6 are respectivelyconnected with three detection control signals EN-G, EN-R/B, and EN-B/Ras switching signals, input terminals of T1-T6 are respectively inputsignals Data R/B, Data G, and Data B/R as detected data, outputterminals of T1-T6 are connected to detection data signal lines CT-G,CT-B/R, and CT-R/B respectively, which is connected to signal lines ofactive display area of the panel by the testing data signal lines toachieve a cell testing process by input data signal Data R/B, Data G,and Data B/R respectively.

When the data line in the panel fails, the panel screen displays anabnormality (a vertical bright line appears), and the existing boxdetecting circuit shown in FIG. 1 is only used as a screen detectingcircuit.

SUMMARY OF INVENTION

A purpose of the application is that for providing an AMOLED panel celltesting circuit and a method for repairing data lines via the AMOLEDpanel cell testing circuit of to overcome a defect of a conventionalcell testing circuit just used as a screen detecting circuit.

In order to achieve the above purposes, the application provides anactive-matrix organic light emitting diode (AMOLED) panel cell testingcircuit, including:

a first switch, wherein a control end of the first switch is connectedto a detection control signal, a first data signal is input into aninput end of the first switch, an output end of the first switch isconnected to a first detection data signal line;

a second switch, wherein a control end of the second switch is connectedto a detection control signal, a second data signal is input into aninput end of the second switch, an output end of the second switch isconnected to a second detection data signal line;

a third switch, wherein a control end of the third switch is connectedto a detection control signal, a third data signal is input into aninput end of the third switch, an output end of the third switch isconnected to a third detection data signal line;

wherein data lines of the panel are divided into first kind of datalines, second kind of data lines, and third kind of data lines accordingto an arrangement mode of a connection to sub pixels, the firstdetection data signal line is connected to the first kind of data lines,the second detection data signal line is connected to the second kind ofdata lines, and the third detection data signal line is connected to thethird kind of data lines;

wherein the first detection data signal line, the second detection datasignal line, and the third detection data signal line include a firstvertical line, a second vertical line, and a third vertical linedisposed correspondingly and placed in two sides of an active displayarea of the panel, and a plurality of first parallel lines, a pluralityof second parallel lines, and a plurality of third parallel linesarranged by a default interval are formed in the active display area ofthe panel and correspondingly connected to the first vertical line, thesecond vertical line, and the third vertical line placed in the twosides.

The sub pixels connected to the first kind of data lines are arrangedalternately by R sub pixels and B sub pixels; the sub pixels connectedto the second kind of data lines are arranged alternately by B subpixels and R sub pixels; and all of the sub pixels connected the thirdkind of data lines are G sub pixels.

When a cell testing process is employed, a solid color/or color barscreen detection process is employed by the first data signal, thesecond data signal, and the third data signal via a clock signal.

The cell testing circuit further is connected to cell testing pads, thecell testing pads are configured to provide the first data signal, thesecond data signal, and the third data signal for the cell testingcircuit.

There are two cell testing pads placed in two sides under the activedisplay area.

A main body is placed upon the active display area.

When an open circuit does not occur in the data lines of the panel, thefirst parallel lines, the second parallel lines, and the third parallellines are not connected to the data lines.

When an open circuit occurs in a certain position of a certain data lineof the panel, one of the first parallel lines, the second parallellines, and the third parallel lines is connected to the certain dataline to repair the open circuit in the certain position.

The application also provides a method for repairing the data lines viathe AMOLED panel cell testing circuit of the above, including:

a step 10 of detecting an open circuit in a certain position of acertain data line in the active display area of the panel via the celltesting circuit;

a step 20 of selecting one selected position in each of two sides of thecertain position of the certain data line, selecting one of the firstparallel lines, the second parallel lines, and the third parallel linesto connect the certain data line at the selected positions to repair theopen circuit in the certain position;

a step 30 of disconnecting the first data signal, the second data signaland the third data signal from the cell testing pads to the cell testingcircuit in a module stage.

The method further includes a step 21 of repeating the step 10 and thestep 20 to repair all of the open circuits of the certain data line.

The method further includes a step 22 of repeating the step 21 to repairseveral open circuits of several data lines in the active display area.

The first parallel line, the second parallel line, and the thirdparallel line are configured for repair the open circuits placed inthree different data lines of the active display area of the panelrespectively.

One of the first parallel line, the second parallel line, and the thirdparallel line is configured for repair the open circuits placed indifferent positions of one of the data lines of the active display areaof the panel.

In conclusion, the AMOLED panel cell testing circuit and the method forrepairing data lines via the AMOLED panel cell testing circuit not onlycan achieve a screen detecting function of the cell testing circuit, butalso achieve to repair the circuit and to improve panel yield.

BRIEF DESCRIPTION OF DRAWINGS

The technical solutions and other beneficial effects of the presentinvention will be apparent from the following detailed description ofembodiments of the invention.

In FIGS.:

FIG. 1 is a schematic diagram of a cell testing circuit in prior art.

FIG. 2a is a schematic diagram of an AMOLED panel cell testing circuitof a preferred embodiment of the application.

FIG. 2b is an equivalent circuit diagram of the AMOLED panel celltesting circuit of the preferred embodiment of the application.

FIG. 3 is a clock signal diagram of the AMOLED panel cell testingcircuit of the preferred embodiment of the application displaying a redscreen.

FIG. 4 is a diagram of positions of a cell testing circuit and a pad ofthe AMOLED panel cell testing circuit of the preferred embodiment of theapplication.

FIG. 5a is a diagram of a connecting type in a panel of the AMOLED panelcell testing circuit of the preferred embodiment of the application.

FIG. 5b is a failure circuit repair principle schematic diagram of theAMOLED panel cell testing circuit of the preferred embodiment of theapplication.

FIG. 5c is a display effect diagram of an abnormal screen of the AMOLEDpanel cell testing circuit of the preferred embodiment of theapplication testing a black screen.

FIG. 5d is a display effect diagram of an abnormal screen of FIG. 5cafter being repaired.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to FIG. 2a , FIG. 2b , and FIG. 2a , FIG. 2a is a schematicdiagram of an AMOLED panel cell testing circuit of a preferredembodiment of the application, FIG. 2b is an equivalent circuit diagramof the preferred embodiment, FIG. 5a is a diagram of a connecting typein a panel of the preferred embodiment. Referring to FIG. 2a , theAMOLED panel cell testing circuit of the application includes:

A first switch SW1, wherein a control end of the first switch isconnected to a detection control signal EN, a first data signal Data R/Bis input into an input end of the first switch, an output end of thefirst switch is connected to a first detection data signal line CT R.

A second switch SW2, wherein a control end of the second switch isconnected to a detection control signal EN, a second data signal DataB/R is input into an input end of the second switch, an output end ofthe second switch is connected to a second detection data signal line CTB.

A third switch SW3, wherein a control end of the third switch isconnected to a detection control signal EN, a third data signal Data Gis input into an input end of the third switch, an output end of thethird switch is connected to a third detection data signal line CT G.

The detection control signal EN can be configured to control severalswitches to connect or disconnect, thereby to control the cell testingcircuit to work or not. The first switch SW1, the second switch SW2, andthe third switch SW3 can be thin film transistors, correspondinglycontrol ends can be gate electrodes of the thin film transistors, andcorrespondingly input ends and output ends can be source electrodes ordrain electrodes of the thin film transistors.

Data lines of a panel are divided into first kind of data lines, secondkind of data lines, and third kind of data lines according to anarrangement mode of a connection to sub pixels. The first detection datasignal line CT R is connected to the first kind of data lines, thesecond detection data signal line CT B is connected to the second kindof data lines, and the third detection data signal line CT G isconnected to the third kind of data lines.

The kinds of the data lines has a relationship with an arranging type ofthe R/G/B of the pixel region, referring to FIG. 2b , in thisembodiment, the arranging type of the R/G/B is that: in the first row,there is a RGBG periodic array, in the second row, there is a BGRGperiodic array, in odd number rows, there are periodic arrays repeatingthe first row, and in even number rows, there are periodic arraysrepeating the second row. In a vertically direction, sub pixelsconnected to the first kind of data line are arranged as R sub pixelsand B sub pixel arranged alternately, sub pixels connected to the secondkind of data line are arranged as R sub pixels and B sub pixel arrangedalternately, and all of sub pixels connected to the third kind of dataline are G sub pixel. In other embodiments, there can be an arrangingtype different from the R/G/B arranging type of FIG. 2b , and notrepeated it here. There are three detection data signal lines, the firstdetection data signal line CT R is connected to the first kind of dataline, the second detection data signal line CT B is connected to thesecond kind of data line, and the third detection data signal line CT Gis connected to the third kind of data line. For the sub pixels arrangedin the first row of the active display area of the panel, a red pixelcircuit is input to the light emitting layer of the first row of theactive display area via the first detection data signal line CT R, ablue pixel circuit is input to the light emitting layer of the first rowof the active display area via the second detection data signal line CTB, and a green pixel circuit is input to the light emitting layer of thefirst row of the active display area via the first detection data signalline CT G. Deciding from the R/G/B arranging type of the preferredembodiment, according to a temporal variation, the first data signalData R/B can be a detection data of a red sub pixel or a blue sub pixel,the second data signal Data B/R can be a detection data of a blue subpixel or a red sub pixel, and the third data signal Data G can be adetection data of a green sub pixel.

Referring to FIG. 5a , the first detection data signal line CT R, thesecond detection data signal line CT B, and the third detection datasignal line CT G comprise a first vertical line 1, a second verticalline 2, and a third vertical line 3 disposed correspondingly and placedin two sides of an active display area (AA) of the panel, and aplurality of first parallel lines, a plurality of second parallel lines,and a plurality of third parallel lines arranged by a default intervaland being perpendicular to the data lines 5 are formed in the activedisplay area of the panel and correspondingly connected to the firstvertical line, the second vertical line, and the third vertical lineplaced in the two sides. When an open circuit does not occur in the datalines 5 of the panel, the first parallel lines, the second parallellines, and the third parallel lines are not connected to the data lines5. And, detection control signals 4 are formed in two sides of theactive display area of the panel to transmit the detection controlsignal EN, and the detection control signal EN can be transmitted from acell testing circuit pad. In the cell testing (CT) circuit of theapplication, the first detection data signal line CT R, the seconddetection data signal line CT B and the third detection data signal lineCT G, there are three signal line, are formed across through the AA areafrom the lines arranged the two sides in an area adjacent to the AAarea, but not connected to the AA area. When an open circuit occurs in acertain position of a certain data line 5 of the panel, one of the firstparallel lines, the second parallel lines, and the third parallel linesis connected to the certain data line 5 to repair the open circuit inthe certain position.

In a conventional AMOLED display device, a conventional CT circuit canbe only used as a circuit used for testing panel display, however, inthe application, the conventional circuit is modified, thereby toachieve a screen detecting function of the cell testing circuit, andwhen the data lines are disabled, the detection signal lines can befused and conducted with the data lines of the panel by a laser weldingprocess, a conventional line defect is modified, there is hardly anydifference between a modified display effect and a display effect of asuperior panel. This improvement design achieves to repair the circuitand to improve panel yield.

Referring to FIG. 3, FIG. 3 is a clock signal diagram of the AMOLEDpanel cell testing circuit of the preferred embodiment of theapplication displaying a red screen, when a red screen is displayed, adetection data Data R input into a red sub pixel of the active displayarea of the panel is a high level, correspondingly, a detection dataData B input into a blue sub pixel of the active display area of thepanel is a low level. In the application, the first data signal DataR/B, the second data signal Data B/R, and the third data signal Data Gcan use a clock signal to achieve a solid color and color bar screendetection, and there is hardly any difference between the display effectand a display effect of a conventional CT circuit detection panel.

Referring to FIG. 4, FIG. 4 is a diagram of positions of a cell testingcircuit and a pad of the AMOLED panel cell testing circuit of thepreferred embodiment of the application. A main body of the cell testingcircuit 100 is placed upon the active display area 101, and a fan outline 102 is used for connecting the data lines of the active displayarea 101 and lines binding between chips of a binding area 103. The celltesting circuit 100 is further connected with a cell testing pad 104.The cell testing pad 104 can be used to provide the first data signalData R/B, the second data signal Data B/R, the third data signal Data G,the detection control signal EN, and so on to the cell testing circuit100. The flexible printed circuit 105 can be used to connect a mainboard of an electrically equipment. In this embodiment, there are twocell testing pads 104 placed in two sides under the active display area101.

According to the AMOLED panel cell testing circuit, the applicationfurther provides a method for repairing data lines via the AMOLED panelcell testing circuit, an innovation point of the application is a new CTcircuit connecting type, thereby to achieve a screen detecting functionof a cell testing circuit and achieve to repair the circuit. In aconventional AMOLED display device, a conventional CT circuit can beonly used as a circuit used for testing panel display; however, in theapplication, the conventional circuit is modified, thereby to achieve ascreen detecting function of the cell testing circuit, and to accuratelydetermine several positions of open circuits, and when the data line isdisabled, the first parallel line, the second parallel line, and thethird parallel line can be fused and conducted with the data lines ofthe panel by a laser welding process, a conventional line defect ismodified, there is hardly any difference between a modified displayeffect and display effect of a superior panel. This improvement designachieves to repair the circuit and to improve panel yield.

Referring to FIG. 5b , FIG. 5b is a failure circuit repair principleschematic diagram of the AMOLED panel cell testing circuit of thepreferred embodiment of the application, and it can be understood withFIG. 5a , FIG. 5c , and FIG. 5d , FIG. 5c is a display effect diagram ofan abnormal screen of the preferred embodiment of the applicationtesting a black screen, FIG. 5d is a display effect diagram of anabnormal screen of FIG. 5c after being repaired. The method forrepairing the data lines of the application includes:

A step 10 of detecting an open circuit in a certain position of acertain data line in the active display area of the panel via the celltesting circuit. When the CT circuit is detecting a black screen, if acertain data line of the AA area is disabled, such as an open circuitoccurs in an a position of the data line, there is no data signal inputto a line being vertical to the a position of the data line, a displayscreen of the panel is a vertical bright line.

A step 20 of selecting one selected position in each of two sides of thecertain position of the certain data line, selecting one of the firstparallel lines, the second parallel lines, and the third parallel linescorrespondingly to the first detection data signal line CT R, the seconddetection data signal line CT B, and the third detection data signalline CT G to connect the certain data line at the selected positions torepair the open circuit in the certain position. A b position and a cposition is selected from two sides of the a position of the data line,a laser welding process is employed to one parallel line of the CTcircuit in the b position of FIG. 5b to make the data signalstransmitted to the circuit of the AA area, there are two same signalstransmitted to the data line in the vertical direction, an abnormalpixel without signals transmitted because of the open circuit ispromoted to a normal pixel with data signals transmitted to the bposition, and in order to make a normal output of a module stage, thelaser welding process is employed to connect the data lines and theparallel line of a periphery of the CT circuit in the c position,thereby to make signals transmit to the parallel line of the CT circuitused as a repairing line.

Further, the method can include a step 21 of repeating the step 10 andthe step 20 to repair all of the open circuits of the certain data line.By a detecting and repeating process of repeating the step 10 and thestep 20 is employed to a certain data line, the application not only canachieve a screen detecting function of the CT circuit, but alsoaccurately determine several positions of open circuits, thereby torepair all of the open circuits of the certain data line. Anyone of thefirst parallel lines, the second parallel lines, and the third parallellines correspondingly to the first detection data signal line CT R, thesecond detection data signal line CT B, and the third detection datasignal line CT G can be used to repair open circuits of differentpositions of one data line in the active display area to repair optionalpositions of one vertical data line.

Further, the method further includes a step 22 of repeating the step 21to repair several open circuits of several data lines in the activedisplay area. By a detecting and repeating process of repeating the step21 is employed to the several data lines the active display area, theseveral data lines the active display area can be repaired. Because theCT circuit includes three kinds of the first parallel lines, the secondparallel lines, and the third parallel lines correspondingly to thefirst detection data signal line CT R, the second detection data signalline CT B, and the third detection data signal line CT G, open circuitsof three data lines of the active display area can be repaired, therebyto repair open circuit of three vertical data lines of the activedisplay area, and for each data line, optional positions of the verticaldata lines can be repaired.

A step 30 of disconnecting the first data signal Data R/B, the seconddata signal Data B/R and the third data signal Data G from the celltesting pads to the cell testing circuit in a module stage. In themodule stage, a laser process is employed to cut signals of the severaldata signal lines from the CT pads to the CT circuit to avoid chips andthe CT pads transmitting signals to CT circuit parallel lines used asrepairing lines and to avoid chip failure. This improvement design ofthe application not only achieve not only can achieve a screen detectingfunction of the CT circuit, but also accurately determine severalpositions of open circuits, thereby to achieve a circuit repairingfunction and improve panel yield.

In a conventional AMOLED display device, a conventional CT circuit canbe only used as a circuit used for testing panel display. If severalopen circuits occur in one data line of the panel (a screen displays avertical bright line) and positions cannot be accurately determined,this design of the application can modified the conventional circuit toachieve a screen detecting function of the cell testing circuit, and toaccurately determine several positions of open circuits and achieve torepair the circuit; and furthermore, when the data line is disabled, theparallel lines can be fused and conducted with the data lines of thepanel by a laser welding process, a conventional line defect ismodified, there is hardly any difference between a modified displayeffect and a display effect of a superior panel. This improvement designachieves to repair the circuit and to improve panel yield.

In the above, various other changes and modifications can be made inaccordance with the technical solutions and technical concept of thepresent invention, and all such changes and modifications should beincluded in the scope of claims.

What is claimed is:
 1. An active-matrix organic light emitting diode(AMOLED) panel cell testing circuit, comprising: a first switch, whereina control end of the first switch is connected to a detection controlsignal, a first data signal is input into an input end of the firstswitch, an output end of the first switch is connected to a firstdetection data signal line; a second switch, wherein a control end ofthe second switch is connected to a detection control signal, a seconddata signal is input into an input end of the second switch, an outputend of the second switch is connected to a second detection data signalline; a third switch, wherein a control end of the third switch isconnected to a detection control signal, a third data signal is inputinto an input end of the third switch, an output end of the third switchis connected to a third detection data signal line; wherein data linesof a panel are divided into first kind of data lines, second kind ofdata lines, and third kind of data lines according to an arrangementmode of a connection to sub pixels, the first detection data signal lineis connected to the first kind of data lines, the second detection datasignal line is connected to the second kind of data lines, and the thirddetection data signal line is connected to the third kind of data lines;wherein the first detection data signal line, the second detection datasignal line, and the third detection data signal line comprise a firstvertical line, a second vertical line, and a third vertical linedisposed correspondingly and placed in two sides of an active displayarea of the panel, and a plurality of first parallel lines, a pluralityof second parallel lines, and a plurality of third parallel linesarranged by a default interval and being perpendicular to the data linesare formed in the active display area of the panel and correspondinglyconnected to the first vertical line, the second vertical line, and thethird vertical line placed in the two sides; and wherein when a celltesting process is employed, a color bar screen detection process isemployed by the first data signal, the second data signal, and the thirddata signal via a clock signal.
 2. The AMOLED panel cell testing circuitof claim 1, wherein the sub pixels connected to the first kind of datalines are arranged alternately by R sub pixels and B sub pixels; the subpixels connected to the second kind of data lines are arrangedalternately by B sub pixels and R sub pixels; and all of the sub pixelsconnected the third kind of data lines are G sub pixels.
 3. The AMOLEDpanel cell testing circuit of claim 1, wherein the cell testing circuitfurther is connected to cell testing pads, the cell testing pads areconfigured to provide the first data signal, the second data signal, andthe third data signal for the cell testing circuit.
 4. The AMOLED panelcell testing circuit of claim 3, wherein there are two cell testing padsplaced in two sides under the active display area.
 5. The AMOLED panelcell testing circuit of claim 4, wherein a main body is placed upon theactive display area.
 6. The AMOLED panel cell testing circuit of claim1, wherein when an open circuit does not occur in the data lines of thepanel, the first parallel lines, the second parallel lines, and thethird parallel lines are not connected to the data lines.
 7. The AMOLEDpanel cell testing circuit of claim 1, wherein when an open circuitoccurs in a certain position of a certain data line of the panel, one ofthe first parallel lines, the second parallel lines, and the thirdparallel lines is connected to the certain data line to repair the opencircuit in the certain position.
 8. A method for repairing the datalines via the AMOLED panel cell testing circuit of claim 1, comprising:a step 10 of detecting an open circuit in a certain position of acertain data line in the active display area of the panel via the celltesting circuit; a step 20 of selecting one selected position in each oftwo sides of the certain position of the certain data line, selectingone of the first parallel lines, the second parallel lines, and thethird parallel lines to connect the certain data line at the selectedpositions to repair the open circuit in the certain position; a step 30of disconnecting the first data signal, the second data signal and thethird data signal from the cell testing pads to the cell testing circuitin a module stage.
 9. The method for repairing the signal lines of claim8 further comprises a step 21 of repeating the step 10 and the step 20to repair all of the open circuits of the certain data line.
 10. Themethod for repairing the data lines of claim 9 further comprises a step22 of repeating the step 21 to repair several open circuits of severaldata lines in the active display area.
 11. The method for repairing thedata lines of claim 8, wherein the first parallel line, the secondparallel line, and the third parallel line are configured for repair theopen circuits placed in three different data lines of the active displayarea of the panel respectively.
 12. The method for repairing the datalines of claim 8, wherein one of the first parallel line, the secondparallel line, and the third parallel line is configured for repair theopen circuits placed in different positions of one of the data lines ofthe active display area of the panel.